Electric snap-switch.



G. B. STEVENS.

ELECTRIC SNAP SWITGH.

APPLICATION FILED 0M. 7, 1909 951,347.. n ed Mar.8, 1910.

zdllllwl- -lllh Inventor His JTttorneg George BStevens,

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UNITED STA ES PATENT OFFICE- enonen E. STEVENS, or LYNN,mnssacrrnsnrrsnssleuon TO GENERAL ELECTRIC:

COMPANY, A CORPORATION 0F 1\TEW YORK.

To all whom it mag concern:

Be it known that I, GEORGE E. STEVENS, a citizen of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented certain new and useful Im rovements in Electric Snap-Switches, of whlch the. following is a specification.

This invention relates to devices for opening and closing electric circuits, and its object is to rovlde a quick-action or snap switch of ow cost, few parts, and durability It consists essentially in a stationary spindlo-shapedmember, having circuit terminal contacts on opposite sides at one end, a gar ter s ring closely encircling the s indle and capa le of completing the circuit between said contacts when it embraces them, and a carrier engaging with said s ring and operating to move it positively om one en of the spindle to the other. As the-carrier proceeds toward the central large diameter of the spindle, the spring is expanded b the conical surface along which it is carrie but the instant it passes the greatest diameter or bilge of the s indle its contractile force urges it towar the end of the spindle, so that its closing upon the contacts is effected -quickly. Conversely, in opening'the switch,

the spring retreats quickly from the neighborhood of the contacts as soon as it passes the bilge of the spindle.

In the accompanying drawing, Figure 1 is a longitudinal section of a switch embodying my invention. Fig. 2 is a plan view with the cover removed. Fig. 3 is an end view, partlybroken away and in section. Fig. 4 is a perspective view of one of the contacts, and Fig. 5 is a perspective view of the spindle.

The casing comprises a body 1 and cover 2 which are molded from porcelain or other insulating material, the bodyhaving a flange 3 at each endcontaining holes 4 for screws by which the switch can be fastened to a support. Extending lengthwise of the casing is a spindle 5 of porcelain or other insulatm material, having at each end a cylindrica head 6 which is held in suitable semicylindrical recesses in the meeting faces of the body and cover, the spindle itself extending from end to end of the interior of the casing.

.A narrow slot 7 runs transversely through the spindle on an axial plane terminatin at the headsfi, and a central longitudinal hole ELECTRIC SNAP-SWITCH.

Serial No. 521,443.

8 extends from end to'end'of said spindle.

In each side of the spindle near one end is formed a shallow recess 9 to receive a sheet metal late 10 forming a'terminal contact. The p atehas a laterally-extending leg 11 resting against the end of the casing and having a bent 'end forming a foot 12 in which: is abinding-screw 13. The feet 12 stand on the bottom of the casing at opposite sides thereofand are secured by screws 14 passingup through the-bottom of the casing.

' Adjacentto each footis ahole 15 through which a line wire can be brought to the binding screw'13. Closely hugging the spindle is a metallic "garter spring 16 and engaging with said spring is acarrier'located in the slot 7 and having arms l7-s'tanding on opposite sides of the spring both above and below the spindle. A push-rod 18 slides freely in atented Mar. s, 191o.

the central bore.8 of the spindle, and the car- 1 rier is fastened to said rod by the pin 19. The rod is of such a length that when the carrier is at either end of the spindle, the adj acent end of the rod projects from the casing, while the other end is fliish with th casing.

In the drawing the switch isshown in the open position. To close it, the rod 18 is pushed to the left, which causes the'carrier to force-the spring 16 over the bilge of the spindle. This expands the spring and puts it under greater tension, so that the instant the bilge is past the contractile energy of the spring is added to the thrust of the rod and sna s the spring onward to the end of the spin e, where 1t closes the circuit between thetwo contacts 10. Should the spring for any reason fail to exert enough force to move the rod and carrier, the push exerted on the rod-by the operator will positively close or open the switch as the case may be. This is a valuable advantage over those switches in which the spring alone is relied upon to effect the actuation of the switch.

-It will be observed that the current divides in two in flowing from contact to contact, each part passing along one-half of the spring, so that the resistance of the spring will not be sufi'icient to prove a detriment. Moreover, its resilience causes it to make a. good electrical connection with the contacts, and its rolling action on the spindle keeps it bright and presents new surfaces of contact at each actuation of the switch. The spring is made of wire large enough to prevent heating and consequent loss of temper.

What I claim as new and desire to secure by Letters Patent of the United States 1s:----

1. In a snap switch, the combination with a stationary spindle, of contacts at one end thereof, a garter spring encircling said spindle and adapted .to connect saidcontacts, and means formoving said spring alon said spindle.

2. n a snap switch, the combination with a stationary spindle having a longitudinal slot,.of contacts at one end of said spindle,

a garter spring encircling said spindle and adapted to connect said contacts, and a carrier movable in said slot and engaging with said s ring.

3. n a snap switch, the combination with a stationary spindle having a longitudinal slot and a central bore, of contacts at one end of said spindle, a garter s ring encircling said spindle, and adapte to connect said contacts, a carrier movable in said slot ti e , and engaging said spring, and a push-rod in said bore secured to said carrier.

4. In a snap switch, the combination with a casing having recesses in each end, of a spindle havin heads received in said rea casing, of a stationary spindle thereinhaving recesses inopposite sides at one end, contacts held in said recesses and having feet secured to the casing and provided with binding screws, a garter spring encircling said spindle, and means for moving said spring lengthwise of said spindle.

In witness whereof, I have hereunto set my hand this fifth day of October, 1909.

' GEORGE'E. STEVENS. Vitnesscs: JOHN A. MGMANUS, Jr.,

CHARLES A. BARNABD. 

